During elevator maintenance, alarm codes displayed on the Monarch elevator controller are important indicators for diagnosing system faults. In many cases, an elevator shutdown is not caused by major hardware failure but by a protection logic triggered by abnormal elevator components. Understanding the meaning of these alarm codes and troubleshooting them based on on-site conditions can often restore elevator operation quickly.

As a long-term supplier of elevator and escalator spare parts serving the global market, A-FLY has found in numerous maintenance projects that more than 70% of drive or main board alarms are related to aging peripheral components or abnormal signals rather than the controller itself.

1. Overcurrent or Overload Alarms

When the control panel displays alarms related to overcurrent or overload, the common causes may include:

Incomplete release of the elevator brake

Abnormal resistance in the traction system

Increased friction between guide shoes and guide rails

Poor heat dissipation of the inverter (VFD)

The recommended troubleshooting approach is to first check whether the mechanical system runs smoothly, then inspect the inverter cooling fan and power module before considering replacement of the main board.

2. Encoder or Speed Feedback Alarms

If the alarm indicates abnormal speed feedback, possible causes include:

Unstable encoder signals

Aging encoder cables

Poor connector contact

Encoder not properly matched with the main controller

These problems usually manifest as vibration during operation or inaccurate leveling. Replacing a compatible encoder and related elevator components can often solve the issue effectively.

3. Door Lock Circuit or Safety Circuit Alarms

When the panel indicates a safety circuit fault, maintenance personnel should first check:

Whether door lock contacts have poor connections

Whether the door operator system runs smoothly

Whether the light curtain or safety edge is falsely triggered

Door lock systems and safety circuits are high-frequency fault areas, and aging components are a common cause of alarms.

4. Power Supply or Control Board Communication Alarms

If communication errors or main board self-check failures occur, the issue may involve:

Unstable power supply to the main control board

Aging power modules

Poor grounding

Loose connections between circuit boards

In such cases, peripheral factors should be ruled out before determining whether the main controller needs replacement.

5. Temperature-Related Alarms

Overheating alarms are more common in summer or in machine rooms with poor ventilation. Possible causes include:

Dust accumulation inside the drive cabinet

Damaged cooling fans

Blocked ventilation channels

Cleaning the cabinet and replacing cooling fan components can significantly reduce the frequency of such alarms.

6. Correct Troubleshooting Order Is More Important Than Blind Replacement

When dealing with Monarch elevator controller alarms, the following troubleshooting principle is recommended:

Confirm that the mechanical system is functioning normally

Check the condition of peripheral elevator components

Finally evaluate the controller or drive unit itself

This outside-to-inside troubleshooting approach can greatly reduce misdiagnosis.

7. Common Mistakes in Maintenance

In actual maintenance work, common mistakes include:

Replacing the main controller immediately after seeing an alarm

Ignoring door systems and safety circuits

Failing to verify encoder model compatibility and parameters

Such mistakes not only increase maintenance costs but may also hide the real cause of the fault.

8. A-FLY Provides Comprehensive Drive System Spare Parts Support

As a professional elevator and escalator spare parts supplier, A-FLY provides:

Encoders and feedback components

Elevator brakes and related electrical parts

Control boards and drive system spare parts

Door lock and safety circuit components

These solutions help maintenance teams quickly identify problems and complete efficient replacements.

Common Monarch Elevator Controller Alarm Codes (NICE Series)

Monarch integrated elevator controllers such as NICE3000 / NICE1000 typically display fault codes on the panel in the format Err + number.

Common Alarm Codes

Err01 – Acceleration overcurrent

Err02 – Deceleration overcurrent

Err03 – Constant-speed overcurrent

Err04 / Err05 / Err06 – Overvoltage

Err07 – Undervoltage

Err08 – Fault shutdown

Err10 / Err11 – Motor overload

Err13 – Absolute encoder fault

Err17 – Star-seal relay fault

Err22 – Safety circuit open

Err24 – Door lock circuit open

1. Inverter / Drive Faults (Err01–Err20)

Err01 / Err02 / Err03 – Overcurrent

Common causes include:

Excessive mechanical load

Output short circuit

Incorrect motor parameter settings

Acceleration time set too short

Err04 / Err05 / Err06 – Overvoltage

Possible causes:

Deceleration time too short

High input voltage

Faulty braking resistor or braking unit

Err07 – Undervoltage

Check for:

Low input power voltage

Phase loss in the power supply

DC bus terminal connection issues

Err10 / Err11 – Motor Overload

Possible causes:

Mechanical blockage

Motor overheating

Incorrect parameter settings

Err13 – Encoder Fault

Check:

Encoder cable connections

Shielded signal wires

Encoder hardware condition

Motor parameter settings

2. System / Safety Circuit Faults (Err21–Err40)

Err22 – Safety Circuit Open

Indicates an open contact in the safety circuit. Check:

Emergency stop switches

Overspeed governor switches

Safety circuit wiring

Err24 – Door Lock Circuit Open

Occurs when the door lock circuit opens during operation. Check:

Door lock contacts

Landing door and car door locks

Err30 – Motor Overheating

Motor thermal protection relay has been triggered.

Err33 – Main Contactor Fault

Check the contactor’s pull-in status and feedback signals.

3. Communication and Door Operator Faults

Err41 – Car Communication Fault

Check CAN communication between the car top board (MCTC-CTB) and the main control board (MCTC-MCB).

Err42 – Landing Communication Fault

Check communication between landing call stations.

Err50 – Door Operator Fault

Possible causes:

Excessive door operator load

Door opening/closing obstruction

Troubleshooting Suggestions

Reset: Try clearing the fault through the operation panel or reset signal.

Check Operating Status: Observe whether the fault occurs during startup, running, or stopping.

Verify Parameters: Check parameter settings related to the fault code (such as motor parameters and acceleration time).

Note: Fault code definitions may vary slightly between different Monarch controller models (such as NICE1000, NICE2000, and NICE3000). Always refer to the specific elevator maintenance manual for accurate details.

Conclusion

Monarch elevator controller alarm codes are essentially early warning signals from the system, rather than simple fault labels. By understanding the logic behind these alarms, analyzing on-site conditions, and replacing key elevator components when necessary, maintenance teams can resolve problems efficiently.

In elevator maintenance and modernization projects, partnering with an experienced spare parts supplier such as A-FLY helps improve troubleshooting efficiency while reducing long-term maintenance costs.